Novel 'injection-only' protocol for sentinel lymph node biopsy in cutaneous melanoma of the distal limbs provides equitable rates of node retrieval and positivity compared to traditional SPECT/CT and lymphoscintigraphy: a prospective comparison study

the validity of this diagnostic method, there is still a lack of detailed data and clinical descriptions directly addressing the standardization of the tracer administration procedure.The aim of the study was a retrospective, single-center comparative analysis of the relationship between the technique and quality of tracer administration and its influence on the accuracy in sentinel node detection.Methods: The analysis covered data collected in one regional Skin Cancer Unit, from March 2020 to January 2025 from all melanoma patients who underwent the SLNB procedure.The analysis considered the methodology of each tracer administration performed in the Department of Nuclear Medicine and compared the amount of tracer delivered by individual physicians with intraoperative lymph node detection rate, using the same equipment by the same surgical team.Results: The study evaluated a total of 595 patients (women n=278 / 46.7%; men n=317 / 53.5%) who underwent a single SLNB procedure following prior labeling with Technetium99.The youngest patient was 18 years old, and the youngest female patient was 24 years old.The maximum age of a male patient was 93 years (mean age 61), while the oldest female patient was 91 years old (mean age 60).The stage of advancement for feature T was as follows: Tx = 30 (5%), T1b = 133 (22,4%), T2a = 102 (17,14%), T2b = 46 (7,7%), T3a = 56 (9,4%, T3b = 80 (13,4%), T4a = 46 (7,7%), T4b = 102 (17,1%).The analysis provided detailed data on the volume of tracer administered during each procedure and the number of personnel performing the procedure from the Department of Nuclear Medicine.The analysis demonstrated differences in the potential detection rates of sentinel nodes.All data were statistically significant (p<0.05).Conclusions: The study demonstrated that despite clear guidelines and a consistently performed SLNB procedure, significant differences may occur in the visualization of lymph nodes.This description represents a preliminary study report, which will be continued.